We have previously demonstrated that ccRCC tumors in this model show intertumor heterogeneity in therapeutic sensitivity to the antiangiogenic agent sunitinib and to the mTOR inhibitor everolimus (34), validating that the model reflects the variable interpatient sensitivities of human ccRCC to 2 clinically used therapies. This evidence concerns the gene MTOR and nonpapillary renal cell carcinoma.